package TreeNode;

public class Main {
    TreeNode n1 = new TreeNode(3); // 根节点 root
    TreeNode n2 = new TreeNode(4);
    TreeNode n3 = new TreeNode(5);
    TreeNode n4 = new TreeNode(1);
    TreeNode n5 = new TreeNode(2);

    //
}
class TreeNode{//二叉树上 值val 左子节点 右子节点
    int val;
    TreeNode left;
    TreeNode right;
    TreeNode(int x){
        val=x;
    }
}